John Isner Is A 'Prince' Of An Endorser

The latest greatest hope for American tennis, six-foot-nine John Isnerwas officially welcomed in as a Prince endorser this morning. Isner, who recently graduated from the University of Georgia, has been playing with Prince's 03 racket technology that has been the buzz of the tennis industry.

The signing is a huge boost to Prince, which hasn't had much luck with the top American men in the game. Andy Roddick uses Babolat and James Blake is back to Dunlop after an endorsement deal with Prince was mutually broken off after Blake couldn't get used to the holes in the racket in the 03.

Tennis insiders say that while the Prince technology is doing well--Prince's $100 million in sales this year will be the best in a decade--and more than 100 WTA and ATP players have switched over the last two years, the one weakness is that the very top players who don't currently use the racket are scared to switch and unlike almost any other racket in the business, the holes can't be faked.

That also hurts players who don't use Prince because their agents can't bluff as well to all the other racket manufacturers that their star players are considering Prince.

With players needing to get used to the racket before agreeing to change their equipment, Prince must work harder than ever before to sign players either earlier on in their careers or get the 03 technology into the hands of young players as soon as possible.

Isner's fast serve has enabled him to rise pretty quickly up the ranks. He made it to the finals of the Legg Mason Classic in D.C. And he took a set of Roger Federer before losing in the third round of the U.S. Open.

Update: A piece of Prince was just bought by private equity firm Nautic. It's believed to be the sixth takeover since the company's inception.